1. Field of the Invention
The present invention relates to solid fuel burners, and in particular burners which include grates that will permit highly efficient burning of materials.
2. Description of the Prior Art
In the prior art, various combustion chamber constructions for burning different materials have been advanced. In particular, burners that use an air suspension for introducing the material to be burned have been shown. U.S. Pat. No. 603,076 shows a burner that suspends fuel particles in an airstream and then introduces the fuel into a burner of substantially conventional design. Entraining the fuel in the fluid stream before the fuel is fed into the furnace is shown in this patent. Also, U.S. Pat. No. 494,375 shows a pulverized fuel feeder that includes an airstream for carrying the fuel into the burner, as does U.S. Pat. No. 3,777,677, which is a waste material burner that suspends products in an airstream and feeds them in a combustion chamber.
U.S. Pat. No. 3,865,053 shows a burner designed for burning sawdust, which includes a form of a venturi through which an airstream entraining the material passes. U.S. Pat. No. 4,311,102 shows a similar arrangement, using an airstream for entraining the materials.
U.S. Pat. Nos. 4,027,602 and 4,184,436 show burners that are used for air entrained combustion materials.
A stacked grate that uses vertically spaced annular rings or plates is shown in U.S. Pat. No. 2,253,694 to Drawz. The rings are placed on top of each over a central fuel feed tube, and coal is forced through the opening and spilled over onto the rings and burned. This includes a deflecting lip at the outer end of the edges of the rings.
However, none of the prior art patents show a burner which provides for the efficient use of a burning material such as pelleted sunflower seed hulls, woodchips, pelleted sawdust, or other biomass materials, in an efficient manner wherein the material is entrained in an airstream and blown into a furnace burner area having generally flat stacked plates along one side, with an adjacent pin hole grate used in combination.